About a month ago, I upgrade my kernel, then this warning message start to appear.
According to this post, I should update the /etc/lvm/lvm.conf and consolidate all the filtering rule into one line, and run vgscan to update the cache. I did all above, but the message still persisted.

Today, I came out the idea that the problem might be resting in my initrd, so I update the initrd using mkinitrd, and it works. The detail step is explained in following paragraph, but beware that:

Of course you need to be root.

Keep the back up initrd image, in case something bad happened.

Need to know how to rescue the system in case something bad really happen.

I have been using Nvidia video card for a while. I’ve tried nv, nouveau, and the proprietary nvidia. I cannot use nouveau because it does not support static rotation yet.

Proprietary nvidia support driect rendering even when the screen is rotated, but Gtk application such as gvim does not reflesh well with it. I have to click on empty lines in gvim to reveal the true nature of the lines!

nv also has it own problem. When starting X, the display area goes rightward and out of the monitor. Indeed monitor’s OSD can move it back, but you have to move it again when play with console mode. How annoying.

Some references kindly tell me that xvidtune address this problem. According to them, you only need to adjust the screen with it, click the “show” button, then paste the output to the xorg.conf. But guess what, I don’t need to post this article if it “JUST-WORK”. It just does not work.

This is the case that Google sucks but man pages rules. 🙂
Google tells you to add “option PreferedMode” which only work for RandR1.2 drivers.
In man 5 xorg.conf, section Screen, subsection Display, option Modes:

They must correspond to those specified or referenced in the appropriate Monitor section (including implicitly referenced built-in VESA standard modes). The server will delete modes from this list which don’t satisfy various requirements. The first valid mode in this list will be the default display mode for startup. ….

Modes don’t have to be in format “<resX>x<resY>” but anything you want.
The “<resX>x<resY>” is for auto-generated Modeline. For your own custom Modeline, better have you own id such as: